Those who cast doubts on the correctness, or indeed existence, of any word should really check before expressing opinions.
The simplest check is to look up the word in a dictionary, for example
abidance.
From there, you will see a link to the use of this word
in context.
There aren't many examples, which suggests that this word is unusual.
What's more, few of the links are to UK or US sources.
As a generalisation, that suggests that "abidance" exists and is in use, but is seldom used by native speakers.
A quick check with the BNC and COCA confirms this.
On that basis, I would advise against using
abidance unless you are certain that your audience will understand and accept it.
BNC - British National Corpus
COCA - Corpus of Contemporary American English